deon_protocol 1.3.4

# Deon Protocol v1.3.4


Repository: [https://github.com/brzb0/Deon-Protocol](https://github.com/brzb0/Deon-Protocol)

A secure, high-performance file transfer and offline value protocol in Rust.

## Features


- **Secure Authentication**: SPAKE2 (Password-Authenticated Key Exchange) prevents MITM.
- **Strong Encryption**: XChaCha20-Poly1305 with 24-byte random nonces (Replay Protection).
- **Offline Economy**: Built-in support for token state management and offline transactions.
- **Smart Handover**: Auto-switch BLE -> Wi-Fi for large files.
- **Resilience**: Token bucket rate limiting, exponential backoff, and session resumption.
- **High-Level API**: One-call helpers for send/receive workflows.

## Architecture


### 1. Token State Management (Offline)

Deon maintains an offline ledger (`economy::Ledger`) to track "Who has how much". Transactions are signed (Ed25519) and verified locally without internet access.

### 2. Replay & Double-Spend Protection

- **Transport Layer**: XChaCha20-Poly1305 uses 24-byte random nonces to prevent replay of encrypted frames.
- **Economic Layer**: Transactions include a monotonic `nonce` checked against the local ledger state to prevent double-spending.

### 3. Settlement Layer

When connectivity is restored, the `SettlementLayer` trait facilitates syncing offline transactions to a blockchain (e.g., Solana, Ethereum) for final validation.

## Installation


From Crates.io:
```bash
cargo install deon_protocol
```

Add as dependency:
```bash
cargo add deon_protocol
```

Or build from source:
```bash
git clone https://github.com/brzb0/Deon-Protocol
cd Deon-Protocol/deon_protocol
cargo build --release
```

## Usage


### CLI


Receive (defaults: `port=8080`, `out=.`):
```bash
deon_protocol receive
```

Send (defaults: `address=127.0.0.1:8080`):
```bash
deon_protocol send "docs.pdf"
```

Custom receiver output directory:
```bash
deon_protocol receive --port 9000 --out ./downloads --password "123456"
```

Custom sender address:
```bash
deon_protocol send "docs.pdf" "192.168.1.50:9000" --password "123456"
```

Environment password fallback:
```bash
set DEON_PASSWORD=123456
deon_protocol receive
```

### Library (Rust) - High-Level


Send with one call:
```rust
#[tokio::main]

async fn main() -> Result<(), deon_protocol::DeonError> {
	deon_protocol::send_file("./docs.pdf", "127.0.0.1:8080", "123456").await?;
	Ok(())
}
```

Receive with one call:
```rust
#[tokio::main]

async fn main() -> Result<(), deon_protocol::DeonError> {
	let saved = deon_protocol::receive_file(8080, "123456", "./downloads").await?;
	println!("Saved file: {}", saved.display());
	Ok(())
}
```

### Library (Rust) - Lower-Level Control


The original lower-level API remains available for advanced integrations:

```rust
use deon_protocol::DeonProtocol;

#[tokio::main]

async fn main() -> Result<(), deon_protocol::DeonError> {
	let mut sender = DeonProtocol::connect("127.0.0.1:8080", "123456").await?;
	sender.send_file_path("./docs.pdf").await?;
	Ok(())
}
```

Economy module remains unchanged and can still be used through `economy::{Transaction, Ledger, SettlementLayer}`.

## Changelog


### v1.3.4

- **API**: Added high-level one-call helpers: `send_file(...)` and `receive_file(...)`.
- **Protocol API**: Added convenience methods `DeonProtocol::connect`, `listen`, `send_file_path`, `receive_file_into`.
- **CLI**: Simplified commands with positional arguments and useful defaults.
- **Docs**: Updated usage examples and onboarding flow.

### v1.3.3

- **Fix**: Moved Session Resumption Ticket creation to immediately after shared secret derivation (server-side).

### v1.3.2

- **Security**: Replaced ChaCha20Poly1305 with XChaCha20Poly1305 (24-byte nonce) to eliminate nonce reuse risks.
- **Protocol**: Fixed Session ID desynchronization; implemented deterministic session ID derivation.
- **Economy**: Added `economy` module with `Transaction`, `Ledger`, and `SettlementLayer` structures.
- **Docs**: Added CONTRIBUTING.md and improved architecture documentation.

### v1.3.1

- Initial release with SPAKE2 and basic file transfer.